OK, that is basically a standard 29g with those dimensions. The dimensions are more important generally. The rasboras are OK, if you want 15 then get them all at once. Shoaling fish always settle in faster the more there are, one beenefit. And for those species that do have an hierarchy or territorial issues (these rasboras don't really, but gourami do) it is even more important. But the rasbora first is good.
I would reconsider the gourami. What other fish are you considering?
So I will order 15 hengeli rasboras for this week, and if you also approve of Alex's food suggestion (bug bites?) then I'll order that straight away so they arrive earlier or at the same time as the fish.
I actually have no clue in regards to other fish ideas. I do like the idea of having fish "layers" (bottom, mid and top dwellers). Although, I don't think top dwellers are a clever idea. The lid of my aquarium has to be fully removed for pretty much everything, it's annoying and bulky. So even with careful supervision and hopefully lots of floating plants soon, there would probably be too many jumping opportunities.
You told me before about substrates and corys. My tank has a small layer of aquasoil and lava rock under the sand, so they probably aren't an option? At least that's what I thought.
Do you have any suggestions for fish?